The present invention relates to a golf club head increased in the joint strength between a main body member and a face member and sole member and having excellent durability.
In recent years, there has been proposed a golf club head in which a constructional element made of a material different from that of the main body member is used in the sole portion, face portion or the like to improve the position of the center of gravity of the head, a moment of inertia of the head and the like. In order to fix such constructional element to the main body member, brazing, soldering or welding is employed according their materials.
For example, in the case of a golf club head (a) which is as shown in FIG. 7 made up of a main body member (b) provided with a face opening (oa) and a sole opening (ob), a face member (c) fixed to the main body member (b) so as to cover the face opening (oa), and a sole member (d) fixed to the main body member (b) so as to cover the sole opening (ob), a conceivable way to fix the members is to braze or solder the face member (c) to the main body member (b) firstly, and then to weld the sole member (d) to the main body member (b).
If the thickness (t) of the sole member (d) is large and the welding requires long time, then the heat during welding transfers to the filler metal (e) fixing the face member (c) to the main body member, therefore, there is a possibility that the joint strength of the face member (c) is decreased. On the other hand, if the thickness (t) of the sole member (d) is decreased to shorten the welding time, then the durability of the sole member (d) and the joint strength of the sole member (d) decrease.